Crystallization kinetics and some physical properties of As-prepared and annealed Ge-Sb-Se chalcogenide glasses

The crystallization kinetics, electrical and optical properties of as-prepa red and annealed GexSb40-xSe60 (22.5 at% less than or equal to x less than or equal to 32.5 at%) chalcogenide system have been studied. The kinetic st udies using differential scanning calorimetry technique and X-ray diffracti on examinations revealed that all the considered glasses can be crystallize d to Sb2Se3 and GeSe2 phases. Electrical conductivity measurements elucidat ed that the GexSb40-xSe60 amorphous thin films behave as semiconductor mate rials especially when the temperature of measurement exceeds a certain valu e which depends slightly on composition. The absorption coefficient-photon energy dependence of the investigated thin films could be described by the Tauc equation. The effect of high annealing temperature on both, the activa tion energy of the electrical conduction and the electronic energy gap have been reported and discussed.